Korg M3: Upgrading the internal SD card with EXB samples

The following procedure is not supported or endorsed by Korg or Karma-Lab. The information is based on unofficial testing performed by members of the user community. It is likely that performing this procedure will invalidate any warranty on your M3.


The original M3 (v2 upgrade) and "old production" XPanded M3 keyboards - e.g. M3-61 and M3-88 - are currently sold with a 256 Mbyte internal SD card and an external "Korg" branded USB stick containing a backup version of the XPanded OS version 2.00 and the EXPCM01, 02 and 03 sample sets. The OS is configured to only load EXPCM03 as default, but you can configure it to auto load all the other EXPCMxx files from the stick if you have the EXB-M 256 memory expansion.

The "new production" XPanded M3 keyboards - e.g. M3M and M3-73 - are currently sold with a 1 GB internal SD card and the EXPCM01, 02, and 03 sample sets are on that card, and they can all auto-load from there. No external USB stick is supplied or required (but you still need the EXB-M 256 card to load more than one of the EXBPCMxx sample files). Eventually all M3's will be sold with a 1 GB internal SD card, but at time of writing we are in a transition period between "old stock" and "new stock".

No Korg M3 XPanded keyboards are shipped as standard with the EXPCM04 sample set loaded, but that file can be downloaded and added by the user.

If you have an M3 XPanded which requires an external USB stick to load the EXB expanded samples, then it is possible to replace the internal 256 Mb SD memory card with a larger capacity card of between 1 GB and 2 GB capacity. The benefit of doing this is that the new XPanded sample sets EXBPCM01, 02, 03 and 04 can be placed on the new card and the OS can be configured to auto-load the files when you power up the M3. No external USB flash memory drive will be required. The downside is that you may invalidate the warranty if you do this.


  1. If your M3 keyboard is running a version of the OS prior to version 2.03 XPanded then you should upgrade to the latest OS first of all.
  2. Your M3 should probably be out of warranty period before you attempt the following procedure. The procedure is not officially supported by Korg and it probably invalidates your warranty.
  3. You need a PC or MAC equipped with an SD card reader/ writer for full size SD cards measuring 3.2 cm by 2.4 cm..
  4. Your M3 must be fitted with the optional EXB-M256 256 Mb RAM expansion board in order for all four sample expansions EXPCM01, 02, 03 and 04 to be used in musical compositions concurrently. Without the EXB-M256 card you can use any one of the four EXPCM** expansions at one time.
  5. You need a 1 GB to 2 GB non-SDHC Secure Digital (SD) card of standard size 3.2 cm by 2.4 cm. The card must be formatted as FAT32. There is a small improvement in system start-up time if you get an SD card rated at 150x or above that is suitable for digital cameras. This Transcend 150x 2GB SD Card performs extremely well.


  1. Remove all cables, connections and plugs from the M3M, including the keybed connector at the base - for safety reasons you MUST remove the mains cable from the socket at the back of the M3M.
  2. Take electro-static discharge (ESD) precautions by either touching an earthed metal object at regular intervals (e.g. a bare copper radiator pipe) or wear an earthed ESD wriststrap, wear no nylon clothing (which is an excellent electrostatic generator), resist any temptation to brush your hair while you are working inside the M3M, and make sure you do not touch any pins or devices or PCB tracks!
  3. In order to replace the internal SD card you have to remove the M3-M from the keyboard assembly (remove the long 1 inch wide metal strip on top of the keyboard - 4 or 5 small screws which will need a good quality correctly sized cross head driver to remove, the screws are a tight fit and they are easy to destroy if you use a badly fitting driver. Remove the hinge mechanism beneath the M3M - 2 screws).
  4. Remove the EXB-RADIAS card if fitted. There are 2 self-tapping metal screws on the base of the M3M securing the large 6 inch by 6 inch cover, and then carefully remove one connector plug that attaches inside the M3 - do not pull the wires of the cable but instead prise the connector plug using a miniature screwdriver. The connector ribbon cable will remain attached to the EXB-RADIAS beneath the metal cover.
  5. Remove the base cover of the M3-M. There are about 16 screws of differing sizes which are all a tight fit, remember where they came from. **In removing the base cover it is likely that you will invalidate any remaining warranty since this is not a supported user procedure.
  6. Remove the old SD card which is visible towards the end of the M3M nearest the power supply (you push it in slightly and then a spring mechanism pops the card out).
  7. Use an SD card reader on a PC or MAC to copy the card contents to a temporary folder on HD. Then you write the exact same contents to the new SD card. Make sure that all files are displayed including "hidden" and "system" files.
  8. On the new SD card it is essential that the write protect tab is in the off (not locked) position. The tab should be towards the contacts edge of the card for it to be unlocked.
  9. Copy the files EXPCM01.KEP EXPCM02.KEP EXPCM03.KEP and EXPCM04.KEP to the top level (root) folder on the new SD card. If you are not sure where to find these files, read this article: Loading EXPCM.KEP sample files
  10. Insert the new card into the slot in the M3M and reassemble everything. Keep the old card complete with contents as backup in case the new card doesn't work!!
  11. Reconnect all cables and connectors, not forgetting the keyboard plug beneath the M3M. Make sure there is no USB flash memory drive plugged into your M3. Turn power on and wait.
  12. After your M3 has powered up, go to MEDIA -> EX-USB-PCM. You will see entries for EXPCM01 EXPCM02 EXPCM03 and EXPCM04 listed in the EX-USB-PCM menu, even though you don't have a USB device plugged in. The XPanded OS has found the files from the newly upgraded internal SD. If you have the EXB-M256 card fitted, you can check all the boxes in the section headed "Auto" and also make sure every file is Loaded (blue status indicator). If you do not have the EXB-M256 card fitted, you can only select one of the four EXPCM** files to auto-load/ load at any one time.
  13. You are done. The selected sample sets will now auto-load from the internal SD card and you will not need to plug in an external USB drive in future.


The internal SD card's extra capacity can only be used to automatically load "sample sets" produced by Korg in the KEP file format. Currently the space requirement for system files and the four EXPCM**.KEP files is just less than 1 GB. If you fit a larger SD card than 1GB then there is no way to use the extra capacity currently. For example, it is not possible to load user samples from the SD card, either automatically or manually. User samples must be manually loaded from a USB device. Auto-loading of user samples (from either USB or the SD Card) is an often-requested "wish-list" item.


Thanks go to user "McHale" for doing all of this on his 1 week old, now probably "out of warranty" M3 and proving it works. The original thread

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